/*
 * idle_win.cpp - detect desktop idle time
 * Copyright (C) 2003  Justin Karneges
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#include <QtGlobal>

#ifdef Q_OS_WIN

	#include "idle.h"
	
	#include <QLibrary>
	#include< windows.h>
	
	/*typedef struct tagLASTINPUTINFO {
		UINT cbSize;
		DWORD dwTime;
	} LASTINPUTINFO, *PLASTINPUTINFO;*/
	
	class IdlePlatform::Private
	{
	public:
		Private()
		{
			GetLastInputInfo = 0;
			IdleUIGetLastInputTime = 0;
			lib = 0;
		}
	
		BOOL (__stdcall * GetLastInputInfo)(PLASTINPUTINFO);
		DWORD (__stdcall * IdleUIGetLastInputTime)(void);
		QLibrary *lib;
	};
	
	IdlePlatform::IdlePlatform()
	{
		d = new Private;
	}
	
	IdlePlatform::~IdlePlatform()
	{
		delete d->lib;
		delete d;
	}
	
	bool IdlePlatform::init()
	{
		if(d->lib)
			return true;
		void *p;
	
		// try to find the built-in Windows 2000 function
		d->lib = new QLibrary("user32");
		if(d->lib->load() && (p = d->lib->resolve("GetLastInputInfo"))) {
			d->GetLastInputInfo = (BOOL (__stdcall *)(PLASTINPUTINFO))p;
			return true;
		}
		else {
			delete d->lib;
			d->lib = 0;
		}
	
		// fall back on idleui
		d->lib = new QLibrary("idleui");
		if(d->lib->load() && (p = d->lib->resolve("IdleUIGetLastInputTime"))) {
			d->IdleUIGetLastInputTime = (DWORD (__stdcall *)(void))p;
			return true;
		}
		else {
			delete d->lib;
			d->lib = 0;
		}
	
		return false;
	}
	
	int IdlePlatform::secondsIdle()
	{
		int i;
		if(d->GetLastInputInfo) {
			LASTINPUTINFO li;
			li.cbSize = sizeof(LASTINPUTINFO);
			bool ok = d->GetLastInputInfo(&li);
			if(!ok)
				return 0;
			i = li.dwTime;
		}
		else if(d->IdleUIGetLastInputTime) {
			i = d->IdleUIGetLastInputTime();
		}
		else
			return 0;
	
		return (GetTickCount() - i) / 1000;
	}

#endif
